That's... not a good rule of thumb to use. It'll be confusing if you try to use the wiki.

Just stick with what's usually cited:
A-frame is usually buffs/debuffs targeting one stat (example exception: Sol's atk debuff is C-frame)
B-frame is usually buffs/debuffs targeting two stats (example exception: Ramiel's Rising Heart is actually A-frame)
C-frame is on the rare side. The stuff that is C-frame tend to be self-buffs, but a bunch of self-buffs are B-frame. It hits a point where you might as well just remember which buffs/debuffs actually are C-frame (like Sol's atk debuff).
Cumulative
Eidolon summon

If nothing else, it's an agreed upon standard to get the idea across, since you'll see this when using the wiki.

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Quote Originally Posted by sanahtlig View Post
It doesn't.
lol gg rip, i'm having belphegor + d'art and amaterasu... all the debuffs are not stackable..... fml